/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2005,2006 INRIA

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 * Modified by Emmanuelle Laprise to remove dependance on LLC headers

 */

#ifndef NET_DEVICE_H

#define NET_DEVICE_H

#include <string>

#include <stdint.h>

#include "ns3/callback.h"

#include "ns3/object.h"

#include "ns3/ptr.h"

#include "address.h"

#include "ipv4-address.h"

#include "ipv6-address.h"

namespace ns3 {

class Node;

class Channel;

class Packet;

/**

 * \ingroup node

 * \defgroup netdevice NetDevice

 */

/**

 * \ingroup netdevice

 *

 * \brief Network layer to device interface

 *

 * This interface defines the API which the IP and ARP

 * layers need to access to manage an instance of a network device 

 * layer. It currently does not support MAC-level 

 * multicast but this should not be too hard to add by adding

 * extra methods to register MAC multicast addresses to

 * filter out unwanted packets before handing them to the

 * higher layers.

 *

 * In Linux, this interface is analogous to the interface

 * just above dev_queue_xmit() (i.e., IP packet is fully

 * constructed with destination MAC address already selected).

 * 

 * If you want to write a new MAC layer, you need to subclass

 * this base class and implement your own version of the

 * NetDevice::SendTo method.

 *

 * This class was designed to hide as many MAC-level details as 

 * possible from the perspective of layer 3 to allow a single layer 3

 * to work with any kind of MAC layer. Specifically, this class 

 * encapsulates the specific format of MAC addresses used by a

 * device such that the layer 3 does not need any modification

 * to handle new address formats. This means obviously that the

 * NetDevice class must know about the address format of all potential 

 * layer 3 protocols through its GetMulticast methods: the current

 * API has been optimized to make it easy to add new MAC protocols,

 * not to add new layer 3 protocols.

 */

class NetDevice : public Object

{

public:

  static TypeId GetTypeId (void);

  virtual ~NetDevice();

  /**

   * \param index ifIndex of the device 

   */

  virtual void SetIfIndex(const uint32_t index) = 0;

  /**

   * \return index ifIndex of the device 

   */

  virtual uint32_t GetIfIndex(void) const = 0;

  /**

   * \return the channel this NetDevice is connected to. The value

   *         returned can be zero if the NetDevice is not yet connected

   *         to any channel or if the underlying NetDevice has no

   *         concept of a channel. i.e., callers _must_ check for zero

   *         and be ready to handle it.

   */

  virtual Ptr<Channel> GetChannel (void) const = 0;

  /**

   * Set the address of this interface

   * \param address address to set

   */

  virtual void SetAddress (Address address) = 0;

  /**

   * \return the current Address of this interface.

   */

  virtual Address GetAddress (void) const = 0;

  /**

   * \param mtu MTU value, in bytes, to set for the device

   * \return whether the MTU value was within legal bounds

   * 

   * Override for default MTU defined on a per-type basis.

   */

  virtual bool SetMtu (const uint16_t mtu) = 0;

  /**

   * \return the link-level MTU in bytes for this interface.

   * 

   * This value is typically used by the IP layer to perform

   * IP fragmentation when needed.

   */

  virtual uint16_t GetMtu (void) const = 0;

  /**

   * \return true if link is up; false otherwise

   */

  virtual bool IsLinkUp (void) const = 0;

  /**

   * \param callback the callback to invoke

   *

   * Add a callback invoked whenever the link 

   * status changes to UP. This callback is typically used

   * by the IP/ARP layer to flush the ARP cache and by IPv6 stack

   * to flush NDISC cache whenever the link goes up.

   */

  virtual void AddLinkChangeCallback (Callback<void> callback) = 0;

  /**

   * \return true if this interface supports a broadcast address,

   *         false otherwise.

   */

  virtual bool IsBroadcast (void) const = 0;

  /**

   * \return the broadcast address supported by

   *         this netdevice.

   *

   * Calling this method is invalid if IsBroadcast returns

   * not true.

   */

  virtual Address GetBroadcast (void) const = 0;

  /**

   * \return value of m_isMulticast flag

   */

  virtual bool IsMulticast (void) const = 0;

  /**

   * \brief Make and return a MAC multicast address using the provided

   *        multicast group

   *

   * RFC 1112 says that an Ipv4 host group address is mapped to an Ethernet 

   * multicast address by placing the low-order 23-bits of the IP address into 

   * the low-order 23 bits of the Ethernet multicast address 

   * 01-00-5E-00-00-00 (hex).  Similar RFCs exist for Ipv6 and Eui64 mappings.

   * This method performs the multicast address creation function appropriate

   * to the underlying MAC address of the device.  This MAC address is

   * encapsulated in an abstract Address to avoid dependencies on the exact

   * MAC address format.

   *

   * A default imlementation of GetMulticast is provided, but this

   * method simply NS_ASSERTS.  In the case of net devices that do not support

   * multicast, clients are expected to test NetDevice::IsMulticast and avoid

   * attempting to map multicast packets.  Subclasses of NetDevice that do

   * support multicasting are expected to override this method and provide an

   * implementation appropriate to the particular device.

   *

   * \param multicastGroup The IP address for the multicast group destination

   * of the packet.

   * \return The MAC multicast Address used to send packets to the provided

   * multicast group.

   *

   * \warning Calling this method is invalid if IsMulticast returns not true.

   * \see Ipv4Address

   * \see Address

   * \see NetDevice::IsMulticast

   */

  virtual Address GetMulticast (Ipv4Address multicastGroup) const = 0;

	/**

   * \brief Get the MAC multicast address corresponding

   * to the IPv6 address provided.

   * \param addr IPv6 address

   * \return the MAC multicast address

   * \warning Calling this method is invalid if IsMulticast returns not true.

   */

  virtual Address GetMulticast (Ipv6Address addr) const = 0;

  /**

   * \brief Return true if the net device is acting as a bridge.

   *

   * \return value of m_isBridge flag

   */

  virtual bool IsBridge (void) const = 0;

  /**

   * \brief Return true if the net device is on a point-to-point link.

   *

   * \return value of m_isPointToPoint flag

   */

  virtual bool IsPointToPoint (void) const = 0;

  /**

   * \param packet packet sent from above down to Network Device

   * \param dest mac address of the destination (already resolved)

   * \param protocolNumber identifies the type of payload contained in

   *        this packet. Used to call the right L3Protocol when the packet

   *        is received.

   * 

   *  Called from higher layer to send packet into Network Device

   *  to the specified destination Address

   * 

   * \return whether the Send operation succeeded 

   */

  virtual bool Send(Ptr<Packet> packet, const Address& dest, uint16_t protocolNumber) = 0;

  /**

   * \param packet packet sent from above down to Network Device

   * \param source source mac address (so called "MAC spoofing")

   * \param dest mac address of the destination (already resolved)

   * \param protocolNumber identifies the type of payload contained in

   *        this packet. Used to call the right L3Protocol when the packet

   *        is received.

   * 

   *  Called from higher layer to send packet into Network Device

   *  with the specified source and destination Addresses.

   * 

   * \return whether the Send operation succeeded 

   */

  virtual bool SendFrom(Ptr<Packet> packet, const Address& source, const Address& dest, uint16_t protocolNumber) = 0;

  /**

   * \returns the node base class which contains this network

   *          interface.

   *

   * When a subclass needs to get access to the underlying node

   * base class to print the nodeid for example, it can invoke

   * this method.

   */

  virtual Ptr<Node> GetNode (void) const = 0;

  /**

   * \param node the node associated to this netdevice.

   *

   * This method is called from ns3::Node::AddDevice.

   */

  virtual void SetNode (Ptr<Node> node) = 0;

  /**

   * \returns true if ARP is needed, false otherwise.

   *

   * Called by higher-layers to check if this NetDevice requires

   * ARP to be used.

   */

  virtual bool NeedsArp (void) const = 0;

  /** 

   * Packet types are used as they are in Linux.  GCC name resolution on 

   * typedef enum {} PacketType is broken for the foreseeable future, so

   * if you need to use ns-3 PacketType in a driver that also uses the 

   * Linux packet types you're hosed unless we define a shadow type, 

   * which we do here.

   */

  enum PacketType

    {

      PACKET_HOST = 1, /**< Packet addressed oo us */

      NS3_PACKET_HOST = PACKET_HOST,

      PACKET_BROADCAST, /**< Packet addressed to all */

      NS3_PACKET_BROADCAST = PACKET_BROADCAST,

      PACKET_MULTICAST, /**< Packet addressed to multicast group */

      NS3_PACKET_MULTICAST = PACKET_MULTICAST,

      PACKET_OTHERHOST, /**< Packet addressed to someone else */

      NS3_PACKET_OTHERHOST = PACKET_OTHERHOST,

    };

  /**

   * \param device a pointer to the net device which is calling this callback

   * \param packet the packet received

   * \param protocol the 16 bit protocol number associated with this packet.

   *        This protocol number is expected to be the same protocol number

   *        given to the Send method by the user on the sender side.

   * \param sender the address of the sender

   * \returns true if the callback could handle the packet successfully, false

   *          otherwise.

   */

  typedef Callback<bool,Ptr<NetDevice>,Ptr<const Packet>,uint16_t,const Address &> ReceiveCallback;

  /**

   * \param cb callback to invoke whenever a packet has been received and must

   *        be forwarded to the higher layers.

   *

   */

  virtual void SetReceiveCallback (ReceiveCallback cb) = 0;

  /**

   * \param device a pointer to the net device which is calling this callback

   * \param packet the packet received

   * \param protocol the 16 bit protocol number associated with this packet.

   *        This protocol number is expected to be the same protocol number

   *        given to the Send method by the user on the sender side.

   * \param sender the address of the sender

   * \param receiver the address of the receiver

   * \param packetType type of packet received (broadcast/multicast/unicast/otherhost)

   * \returns true if the callback could handle the packet successfully, false

   *          otherwise.

   */

  typedef Callback< bool, Ptr<NetDevice>, Ptr<const Packet>, uint16_t,

                    const Address &, const Address &, enum PacketType > PromiscReceiveCallback;

  /**

   * \param cb callback to invoke whenever a packet has been received in promiscuous mode and must

   *        be forwarded to the higher layers.

   * 

   * Enables netdevice promiscuous mode and sets the callback that

   * will handle promiscuous mode packets.  Note, promiscuous mode

   * packets means _all_ packets, including those packets that can be

   * sensed by the netdevice but which are intended to be received by

   * other hosts.

   */

  virtual void SetPromiscReceiveCallback (PromiscReceiveCallback cb) = 0;

  /**

   * \return true if this interface supports a bridging mode, false otherwise.

   */

  virtual bool SupportsSendFrom (void) const = 0;

};

} // namespace ns3

#endif /* NET_DEVICE_H */